CheckBox DataBinding bug?

[Istvan Bagyura]

Hi!

I have a problem with a bound CheckBox when I want to insert a new row.

I bound the cbox to a bit type field ( MS SQL SERVER). It works fine when I want to navigate through the table or I want to modify the values.
But when I'd like to insert a new row and I want to navigate to this newly inserted row I can't.
It simply don't work. Without the checkbox it works fine.

Here is some code:
// the databinding
// chkAdmin is a CheckBox
// dvEmpGroup is a DataView
chkAdmin.DataBindings.Add( "Checked" , dvEmpGroup , "isAdmin" ) ;

// insert a new row and locate it.
// dvEmpGroup is a DataView
// newRec is a DataRowView
newRec = dvEmpGroup.AddNew() ;
BindingContext[ dvEmpGroup ].Position = BindingContext[ dvEmpGroup ].Count ;

I guess the problem with the default value of the bound DB field. (What can do a checkbox with a null value?)If I'm right how can I set the default value of a field in a datasource from code?

If you know the answers pls write me.

Hi!

B.I.

[Chad Cothern]

I had the same exact problem. I was binding a List box to the same data set as my text boxes so that the list box would control the bindingcontext position. I thought that maybe the problem was the combination of the two controls (one with complex binding and the collection of simple bound text boxes). When I read your message, I realized that I had overlooked my checkbox control. That was definitely it! The database was set to automatically default to 1/True, but you also have to make sure that this is set in your .xsd schema of your dataset (if you use one). In design view of the xsd file, you can select the field and in the Properties window, set default to "true" or "false". It didn't seem to like 1 or 0, or even "True" or "False". It MUST be lowercase to work. After that, my .addnew added the row and automatically pointed to the new record (as it should).
If you aren't using a strongly typed dataset (.xsd) then you can set the default by using the following syntax (or something of the equivalent):

datasetname.Tables("tablename").Columns("columnname").DefaultValue = "true"

Thanks for your post, it helped me solve my problem!

> Hi!
>
> I have a problem with a bound CheckBox when I want to insert a new row.
>
> I bound the cbox to a bit type field ( MS SQL SERVER). It works fine when I want to navigate through the table or I want to modify the values.
> But when I'd like to insert a new row and I want to navigate to this newly inserted row I can't.
> It simply don't work. Without the checkbox it works fine.
>
> Here is some code:
> // the databinding
> // chkAdmin is a CheckBox
> // dvEmpGroup is a DataView
> chkAdmin.DataBindings.Add( "Checked" , dvEmpGroup , "isAdmin" ) ;
>
>
> // insert a new row and locate it.
> // dvEmpGroup is a DataView
> // newRec is a DataRowView
> newRec = dvEmpGroup.AddNew() ;
> BindingContext[ dvEmpGroup ].Position = BindingContext[ dvEmpGroup ].Count ;
>
> I guess the problem with the default value of the bound DB field. (What can do a checkbox with a null value?)If I'm right how can I set the default value of a field in a datasource from code?
>
> If you know the answers pls write me.
>
> Hi!
>
> B.I.

[Kris_xx]

I also had the same problem and i managed to over come using event handler

add the following code segment to initial binding procedure

dBindins = New Binding("checked", ds.Tables(0), "RoadTest")

AddHandler dBindins.Format, AddressOf FormatHandler

CheckBox2.DataBindings.Add(dBindins)

then create a cutom procedure call FormatHandler and add the following segment

Public Sub FormatHandler(ByVal sender As Object, ByVal e As ConvertEventArgs)
If IsDBNull(e.Value) Then
e.Value = False
End If
End Sub

when u adding a new record this will check for DBNull and make as Fale

Kris_xx